Theories are not discoveries but inventions of humans, usually meant to formally describe regularities in experience, which often bring forth new ways of experiencing. (The music-making itself ('practice'), if at odds with existing theories, may provoke the creation of new theories; it is thus important to recognize that theory and practice mutually and reciprocally influence each other.)
There is a great deal of theory around the creation and/or discovering of tunings, scales, and temperaments, but whether it is useful to bother learning any of them is a matter of personal decision. (It is always possible to load up a random tuning on your retunable instrument of choice and explore it through music, without bothering to understand the theoretical considerations that led to the construction and/or discovery of said tuning.) Below you will find a partial list of currently-established theories related to alternative intonations.
Reality tunnels into microtonality
Just Intonation: an infinite world of rational numbers and numerous models: the harmonic series, integer frequency ratios, tonality diamonds, eikosany, etc.
Equal tunings: each one a subtle monoculture of intervals. May be treated as temperaments, or not
In Western common practice music, the (somewhat forgotten) use of historical temperaments (meantones, well temperaments) with 12 or more unequal notes per octave
Musical traditions of indigienous, ancient, and/or non-Western cultures
Regular Temperaments (including Linear Temperaments): a centuries-old practice that has recently undergone a mathematical facelift, in which Just Intonation is selectively and regularly detuned in various ways, to better meet a variety of compositional desires
Moment of Symmetry, a means of iterating a single generative interval, modulo a period interval, to produce scales of two step-sizes. Brought to you by Erv Wilson
Graham complexity, a complexity measure which works well with MOS scales and rank two regular temperaments.
Empirical This is a form of hands-on, field research as opposed to a form of acoustical or scale engineering where tunings are specifically derived from listening and playing experiments carried out in the pitch continuum.
Tetrachordal Scales, which use divided fourths as building blocks for composition.
Tonalsoft Encyclopedia of microtonal music theory - a whole sea of information on the topic, covering both historical tuning theories and modern developments
Theory: Inventions that shape understanding
Theories are not discoveries but inventions of humans, usually meant to formally describe regularities in experience, which often bring forth new ways of experiencing. (The music-making itself ('practice'), if at odds with existing theories, may provoke the creation of new theories; it is thus important to recognize that theory and practice mutually and reciprocally influence each other.)
There is a great deal of theory around the creation and/or discovering of tunings, scales, and temperaments, but whether it is useful to bother learning any of them is a matter of personal decision. (It is always possible to load up a random tuning on your retunable instrument of choice and explore it through music, without bothering to understand the theoretical considerations that led to the construction and/or discovery of said tuning.) Below you will find a partial list of currently-established theories related to alternative intonations.
Reality tunnels into microtonality
External links